Re: ZFS command can block the whole ZFS subsystem!

From: Adam Vande More <amvandemore_at_gmail.com>
Date: Sun, 5 Jan 2014 06:43:18 -0600
On Sun, Jan 5, 2014 at 2:11 AM, O. Hartmann <ohartman_at_zedat.fu-berlin.de>wrote:

> On Sun, 5 Jan 2014 10:14:26 +1100
> Peter Jeremy <peter_at_rulingia.com> wrote:
>
> > On 2014-Jan-04 23:26:42 +0100, "O. Hartmann"
> > <ohartman_at_zedat.fu-berlin.de> wrote:
> > >zfs list -r BACKUP00
> > >NAME              USED  AVAIL  REFER  MOUNTPOINT
> > >BACKUP00         1.48T  1.19T   144K  /BACKUP00
> > >BACKUP00/backup  1.47T  1.19T  1.47T  /backup
> >
> > Well, that at least shows it's making progress - it's gone from 2.5T
> > to 1.47T used (though I gather that has taken several days).  Can you
> > pleas post the result of
> > zfs get all BACKUP00/backup
> >
>
> Here we go:
>
>
> NAME             PROPERTY              VALUE                 SOURCE
> BACKUP00/backup  type                  filesystem            -
> BACKUP00/backup  creation              Fr Dez 20 23:17 2013  -
> BACKUP00/backup  used                  1.47T                 -
> BACKUP00/backup  available             1.19T                 -
> BACKUP00/backup  referenced            1.47T                 -
> BACKUP00/backup  compressratio         1.00x                 -
> BACKUP00/backup  mounted               no                    -
> BACKUP00/backup  quota                 none                  default
> BACKUP00/backup  reservation           none                  default
> BACKUP00/backup  recordsize            128K                  default
> BACKUP00/backup  mountpoint            /backup               local
> BACKUP00/backup  sharenfs              off                   default
> BACKUP00/backup  checksum              sha256                local
> BACKUP00/backup  compression           lz4                   local
> BACKUP00/backup  atime                 on                    default
> BACKUP00/backup  devices               on                    default
> BACKUP00/backup  exec                  on                    default
> BACKUP00/backup  setuid                on                    default
> BACKUP00/backup  readonly              off                   default
> BACKUP00/backup  jailed                off                   default
> BACKUP00/backup  snapdir               hidden                default
> BACKUP00/backup  aclmode               discard               default
> BACKUP00/backup  aclinherit            restricted            default
> BACKUP00/backup  canmount              on                    default
> BACKUP00/backup  xattr                 on                    default
> BACKUP00/backup  copies                1                     default
> BACKUP00/backup  version               5                     -
> BACKUP00/backup  utf8only              off                   -
> BACKUP00/backup  normalization         none                  -
> BACKUP00/backup  casesensitivity       sensitive             -
> BACKUP00/backup  vscan                 off                   default
> BACKUP00/backup  nbmand                off                   default
> BACKUP00/backup  sharesmb              on                    local
> BACKUP00/backup  refquota              none                  default
> BACKUP00/backup  refreservation        none                  default
> BACKUP00/backup  primarycache          all                   default
> BACKUP00/backup  secondarycache        all                   default
> BACKUP00/backup  usedbysnapshots       0                     -
> BACKUP00/backup  usedbydataset         1.47T                 -
> BACKUP00/backup  usedbychildren        0                     -
> BACKUP00/backup  usedbyrefreservation  0                     -
> BACKUP00/backup  logbias               latency               default
> BACKUP00/backup  dedup                 on                    local
>

As already described by Dan and perhaps not followed up on:  dedup requires
at very large amount of memory.  Assuming 32GB is sufficient is most likely
wrong.

What does zdb -S BACKUP00 say?

Also I will note you were asked if the ZFS FS in question had dedup
enabled.  You replied with a response from an incorrect FS.



-- 
Adam
Received on Sun Jan 05 2014 - 11:43:19 UTC

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